Conventional medical imaging systems used in the imaging of blood vessel interiors typically include a guidewire and a catheter. The guidewire is usually inserted into the blood vessel and then advanced to the area of interest using an external imaging technique such as fluoroscopy. Once in place, the catheter is routed over the guidewire and into proximity with the area of interest, which may be a diseased tissue region such as a blood vessel occlusion or plaque, a deployed interventional device such as a stent, or any other area of interest. The catheter can include one or more imaging devices for imaging the area of interest. The catheter can also be configured to perform one or more interventional therapies to the area of interest. Typical imaging catheters have forward looking and/or side looking imaging capabilities, i.e., the catheter is capable of imaging a region distal to the catheter and/or a region along side a longitudinal axis of the catheter, respectively. Typical interventional therapies include tissue ablation, drug delivery or the use of an interventional device such as a balloon or a stent, etc.
Before administering an interventional therapy, it is desirable to obtain an image of the area of interest to locate, for instance, the diseased tissue and characterize the tissue type so that the proper interventional therapy can be chosen and administered. This is commonly performed with the aid of an imaging catheter. In cases where the blood vessel is weakened or in an serious disease state, advancement of the catheter into proximity with the diseased tissue increases the risk of the blood vessel being injured or ruptured. This risk is even greater when operating within narrow vasculature having thin vessel walls that are more susceptible to injury.
Accordingly, there is a need for smaller intravascular imaging systems capable of imaging within narrow vasculature with a reduced risk of injury.